/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
using System;
using System.Collections;

namespace Thrift.Collections
{
	public class TCollections
	{
		/// <summary>
		/// This will return true if the two collections are value-wise the same.
		/// If the collection contains a collection, the collections will be compared using this method.
		/// </summary>
		public static bool Equals (IEnumerable first, IEnumerable second)
		{
			if (first == null && second == null)
			{
				return true;
			}
			if (first == null || second == null)
			{
				return false;
			}
			IEnumerator fiter = first.GetEnumerator ();
			IEnumerator siter = second.GetEnumerator ();

			bool fnext = fiter.MoveNext ();
			bool snext = siter.MoveNext ();
			while (fnext && snext)
			{
				IEnumerable fenum = fiter.Current as IEnumerable;
				IEnumerable senum = siter.Current as IEnumerable;
				if (fenum != null && senum != null)
				{
					if (!Equals(fenum, senum))
					{
						return false;
					}
				}
				else if (fenum == null ^ senum == null)
				{
					return false;
				}
				else if (!Equals(fiter.Current, siter.Current))
				{
					return false;
				}
				fnext = fiter.MoveNext();
				snext = siter.MoveNext();
			}

			return fnext == snext;
		}

		/// <summary>
		/// This returns a hashcode based on the value of the enumerable.
		/// </summary>
		public static int GetHashCode (IEnumerable enumerable)
		{
			if (enumerable == null)
			{
				return 0;
			}

			int hashcode = 0;
			foreach (Object obj in enumerable)
			{
				IEnumerable enum2 = obj as IEnumerable;
				int objHash = enum2 == null ? obj.GetHashCode () : GetHashCode (enum2);
				unchecked
				{
					hashcode = (hashcode * 397) ^ (objHash);
				}
			}
			return hashcode;
		}
	}
}